<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>mycss3</title>
    <style>
        span {
            width: 300px;
            height: 100px;
            background-color: silver;
            display: block;
            border: 1px solid blue;
        }
    </style>
</head>
<body>
<span>达内云计算学院</span>
<span>nsd cloud computing</span>
</body>
</html>